The present invention relates to a side airbag apparatus that protects an occupant seated in a vehicle seat by deploying and inflating an airbag on a side of the occupant when an impact is applied to the vehicle from the side of the vehicle seat.
A side airbag apparatus having an airbag and a gas generator is effective as an apparatus that protects an occupant seated in an automobile seat when an impact is applied to the seat from a side, for example, due to a side collision.
For example, Japanese Laid-Open Patent Publication No. 2015-30322 discloses a side airbag apparatus shown in FIGS. 16 and 17, which includes an airbag 120. The outer envelope of the airbag 120 is formed by an airbag main body 122. The interior of the airbag main body 122 is divided into an upper inflation chamber and a lower inflation chamber 124, which is located below the upper inflation chamber, by a lateral partition 123, which extends in the front-rear direction.
The upper inflation chamber is divided into an upper-rear inflation chamber 128 and an upper-front inflation chamber 127 by a vertical partition 126, which extends vertically and has a communication portion 125. The upper-rear inflation chamber 128 receives inflation gas from a gas generator 121. The upper-front inflation chamber 127 is located on the front side of the upper-rear inflation chamber 128 and receives inflation gas via the communication portion 125.
An inner tube 129 is provided at the rear end in the airbag main body 122. The inner tube 129 extends vertically and bridges the upper-rear inflation chamber 128 and the lower inflation chamber 124. The inner tube 129 regulates the flow of inflation gas from the gas generator 121 to direct the flow toward the upper-rear inflation chamber 128 and the lower inflation chamber 124. The lower part of the inner tube 129 configures a check valve 130. The check valve 130 allows inflation gas to flow from the upper-rear inflation chamber 128 to the lower inflation chamber 124, but restricts flow in the opposite direction, or the flow of inflation gas from the lower inflation chamber 124 to the upper-rear inflation chamber 128.
The above described side airbag apparatus inflates the lower inflation chamber 124, the upper-rear inflation chamber 128, and the upper-front inflation chamber 127 with appropriate internal pressures to effectively protect the upper body of the occupant against impacts.
In the above described side airbag apparatus, the inner tube 129 and the vertical partition 126 are configured by a single fabric piece 131. The fabric piece 131 is folded in half at the center to form a pair of fabric portions 132, 133. Each of the fabric portions 132, 133 has a vertical joint portion 134 at the middle section in the front-rear direction. The vertical joint portions 134 extend vertically to form the inner tube 129 on the rear side of the vertical joint portions 134. Also, the vertical partition 126 is formed on the front side of the vertical joint portions 134.
However, since the inner tube 129 and the vertical partition 126 are formed by the single fabric piece 131 in the side airbag apparatus of Japanese Laid-Open Patent Publication No. 2015-30322, the location at which the vertical joint portion 134 is formed cannot be easily determined. That is, the vertical joint portion 134 cannot be easily positioned. As a result, it is difficult to form the vertical joint portions 134 accurately at predetermined locations on the folded fabric portions 132, 133. That is, it is difficult to accurately join the vertical partition 126 to the inner tube 129.